Depression or adjustment disorder is often underdiagnosed in patients with cancer

Depression is often hidden within clusters of symptom responses to treatment and the burden of cancer, such as pain, fatigue, sleep disturbance, and cognitive changes

Early diagnosis and management of depression in cancer patients may contribute to improving quality of life and treatment adherence

Research on emotional distress includes its role in tumor progression and increased risk of cancer mortality

Background

A diagnosis of cancer is a life-altering event and carries with it both physical and psychological burdens. Measuring response to an individual’s psychological burden of cancer is difficult and may be nonexistent. Depression, for example, may be masked within clusters of treatment responses, making it difficult to diagnose and treat.1-3Recent studies suggest that depression may be a risk factor in cancer progression1,2,4 and may increase the risk of death.4 Clinicians, patients and family members may not recognize depression; therefore assessment for depression should be part of baseline and ongoing examinations.5

Diagnosing Depression

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) classifies depression as an adjustment disorder, symptoms of which may include6,7

Depressed mood (feelings of sadness)

Loss of interest or pleasure

Sleep disturbances

Loss of energy or feelings of fatigue

Difficulty in concentrating or decision making

Appetite or weight changes

Psychomotor agitation or psychomotor retardation

Feelings of worthlessness or excessive guilt

Suicidal thoughts or intentions

Diagnostic criteria for depression are the core symptom (depressed mood) plus 4 of the other symptoms lasting for at least 2 weeks and occurring on most days, except for thoughts of suicide or death.7
Depression is often underdiagnosed because of many factors, including8

In patients with cancer, a number of physical manifestations or treatment-related symptoms may contribute to the somatic symptoms of depression, making this diagnosis challenging.9 Sadness and grief are normal reactions during any stage of cancer, but many studies show a higher prevalence of depression with advanced disease. The prevalence of major depression and depressive symptoms ranges widely, from 1% to 42%3—an estimated 2 to 3 times that in the general population.5,9,10

Table 1. Risk Factors for Depression

Cancer-Related Risk Factors

Non–Cancer-Related Risk Factors12,13

Depression at diagnosis

Prior history of depression; past treatment of psychological disorders

Assessment
Depression can affect quality and meaning of life in patients with cancer, so timely diagnosis and management are crucial. There is no consensus on a single assessment technique, but combinations of 3 approaches should be considered: self-report, response to simple questions, and/or brief screening instruments and clinical interview (the latter considered the most effective).2

Self-Report: Simple Questions
In addition to asking about somatic symptoms, which are not specific to depression, asking patients how often they feel depressed or hopeless helps identify those at risk. Additional questions about lack of interest or pleasure in daily living and activities may be useful in detecting core symptoms.8 Other questions may be asked:

How are you sleeping?

How would you describe your mood or energy level over the past 2 weeks?15

The fear of cancer and its potential consequences is very real, yet admitting to feeling depressed or down may carry a stigma. Patients may fear their depression is a sign of weakness and inability to tolerate treatment—they may even fear withdrawal of treatment.3,12 Because of the potential stigma, the National Comprehensive Cancer Network (NCCN) Panel uses the more neutral term “distress” to characterize psychosocial symptoms.16

Self-Report: Screening Instruments
Structured instruments and symptom scales may be useful in diagnosing major depression and its severity over a specific time period. In clinical settings, drawbacks of some instruments include time to administer and score. Relatively brief but validated questionnaires may be the preferred choice for routine screening of cancer patients’ emotional distress. Brief self-reports are easy to administer, inexpensive (some are even free), and, if properly validated, can help identify those patients most in need of professional mental health support. A systematic review of assessment tools to screen for emotional distress in people with cancer was published by Vodermaier, Linden and Siu. Included in the review are both newly developed and well-established distress screening tools that have been validated in patients with cancer.17

Table 2. Examples of Self-Report Screening Tools

Name

Comments

Diagnostic and Statistical Manual of Mental Disorders6-8

Widely held standard for assessing other tools

Hospital Anxiety and Depression Scale (HADS)5,18

14-item measure of psychological distress,

perhaps most frequently used

Brief Symptom Inventory (BSI-18)5

18-item overview of a patient's symptoms and intensity at specific point in time

Distress Thermometer5,16

Single-item rating of distress on a scale of 1-10 (no distress to extreme distress). From a checklist of 5 categories, patients select what may have been the possible source of their distress

Zung Self-Rating Depression Scale9

20-item scale that measures the severity of depression

Beck Depression Inventory (BDI)2

21-item inventory that reduces influence ofsomaticconcerns

BriefEdinburghDepression Scale (BEDS)19

6-item measure of depression in cancer patients

Clinical or Diagnostic Interview12

Screening tools can help determine need for follow-up or referral to the most appropriate mental health professional. Acute or severe depression with risk of suicidal thoughts warrants immediate psychiatric intervention.11 The oncologist, advanced practice nurse, or psychiatrist may order drug therapy; social workers, psychiatric liaison nurses, or clergy may guide patients in identifying the stressors of cancer and its treatment.

Clinical Practice Guidelines

The National Comprehensive Cancer Network (NCCN) practice guidelines for distress management advise an assessment initially and at appropriate intervals. The guidelines suggest timing interventions based on the patient’s “distress thermometer” responses. http://www.nccn.org/professionals/physician_gls/PDF/distress.pdf Accessed February 9, 2010.

Treatment Options
Pharmacology Overall, there is limited evidence of clinical trials specifically studying pharmacologic treatment of depression in cancer patients.10,18 There is no record of randomized, controlled studies of alternative medicine interventions.18 For pharmacologic treatment of cancer-related depression, consider the following:

If prior therapy for depression was successful, start with the same agent8

Selective serotonin reuptake inhibitors (SSRIs) are considered agents of choice due to low side effects8

Antidepressants should be started at low doses to decrease potential side effects and interaction with cancer therapy, then titrated upward to effect15

Instruct patients to report use of herbals to avoid dangerous drug interactions15

Psychosocial or PsychoeducationalEvidence exists that psychosocial or psychoeducational interventions are beneficial for depression in patients with cancer and are often combined with pharmacologic therapy.8,18,20,21 Traditional psychotherapy is not recommended, since patients dealing with cancer often cannot commit to self-exploration.11 Cognitive-behavioral concepts are considered effective because

Thoughts (not events, people, or circumstances) such as those that accompany hearing the diagnosis of cancer can influence feelings and behaviors8

Changing thoughts can ameliorate depressive feelings, even if the situation does not change

Group and individual settings can be beneficial

Team members can address negative thoughts by reframing the thoughts and giving context to behaviors, since they have long-term relationships with cancer patients9

Outcomes are measurable, with change evident in a short time period

A challenge for both oncology nurses and patients is the use of oral antidepressants with patients seen infrequently, making psychosocial assessment and appropriate intervention difficult. In this situation, communication with the patient’s primary healthcare provider is essential.

An integrated approach to recognizing and managing depression in people with cancer may have better outcomes than medication or counseling alone. A study by University of Edinburgh researchers studied 200 cancer patients who scored high for depression on a baseline screening exam. Participants were randomized to an intervention group (n=101) that included usual care plus participation in a program given by specially-trained cancer nurses. The intervention emphasized screening for depression, antidepressant medication, and teaching patients problem-solving skills. The control group (n=99) received usual care. At 3 months, scores for depression fell in both groups, though by a significantly greater amount in the group working with the nurses. The results at 6- and 12-months follow-up reflected similar findings. In both groups, there was a significant increase in antidepressant use. Patients in the intervention group reported less anxiety and fatigue at both 3 and 6 months compared to those receiving usual care only.22

Nursing Management

Depression may coexist with other symptoms: identifying them and planning their management may relieve a depressed mood. Deviation from routines or habits is very individual, with self- reporting either over or under the actual deviation from normal routine.

Pain—frequent contributor to depression, which cannot be controlled if pain persists.9,11 The WHO 3-step analgesic ladder is useful for pain relief 3

Depression is the most frequently studied psychological condition in patients with cancer.2 Nevertheless, its screening is not routine, so depression remains underrecognized, and undertreated. Areas of needed research on depression in cancer are

Nutrition and the role of omega-3 fatty acids12

Tumor biology causing inflammation as an inducer of behavior changes, such as fatigue leading to depression8,14

Neuroendocrine, neuroimmune, neurochemical alterations1,2,8,9

Antidepressant drug therapy, including polypharmacy, in patients with cancer and comorbid conditions

Stress as an inducer of tumor growth through cytokine activity14

Red cell folate levels and synthesis of monoamines, a class of antidepressants12